[kubeadm] Adds json struct tags to exposed API types

Signed-off-by: Chuck Ha <[email protected]>

Author: chuckha

cmd/kubeadm/app/apis/kubeadm/v1beta1/bootstraptokenstring.go

@@ -31,8 +31,8 @@ import (
 // of view and as an authentication method for the node in the bootstrap phase of
 // "kubeadm join". This token is and should be short-lived
 type BootstrapTokenString struct {
-	ID     string
-	Secret string
+	ID     string `json:"-"`
+	Secret string `json:"-"`
 }
 
 // MarshalJSON implements the json.Marshaler interface.

cmd/kubeadm/app/apis/kubeadm/v1beta2/bootstraptokenstring.go

@@ -31,8 +31,8 @@ import (
 // of view and as an authentication method for the node in the bootstrap phase of
 // "kubeadm join". This token is and should be short-lived
 type BootstrapTokenString struct {
-	ID     string
-	Secret string
+	ID     string `json:"-"`
+	Secret string `json:"-"`
 }
 
 // MarshalJSON implements the json.Marshaler interface.